This article presents a lesson plan that uses materials such as rope, drinking water, and straws in a classroom activity to teach elementary students about electrical circuits in a "hands on/minds on" fashion. Students first experiment with bulbs, wires, and switches, then they do an activity with simulating electricity through a circuit…

Electron-atom collisions in gases are an aspect of atomic physics. Three experiments in this field employing a thyratron are described: (i) the Ramsauer-Townsend effect, (ii) the excitation and ionization potentials of xenon and (iii) the ion-electron recombination after interrupting the electric discharge.

Catt's anomaly is a sort of "thought experiment" (a "gedankenexperiment") where electrons seem to travel at the speed of light. Although its author argued with conviction for many years, it has a clear and satisfactory solution and it can be considered indubitably just an apparent paradox. Nevertheless, it is curious and…

In this article we examine cases of more classical and less classical nature compared to results found by quantum mechanics and attribute a form of Free Energy discontinuity for each case within a boundary layer. The concept of a boundary layer is broadened as to include areas of first or second variations of the Gibbs free energy. It is…

An alternative method of presenting the second law of thermodynamics in introductory courses is presented. The emphasis is on statistical approaches as developed by Atkins. This has the benefit of stressing the statistical nature of the law.

In learning chemistry at the entry level, many learners labor under misconceptions about the subject matter that are so fundamental that they are typically never addressed. A fundamental misconception in chemistry appears to arise from an adding of existing phenomenal concepts to newly-acquired chemical concepts, so that beginning learners think…

Chemistry possesses a distinctive theoretical lens--a distinctive set of theoretical concerns regarding the dynamics and transformations of a perplexing variety of organic and nonorganic substances--to which it must be faithful. Even if it is true that chemical facts bear a special (reductive) relationship to physical facts, nonetheless it will…

This paper is about new contents that can be introduced into science education. It is a description of an experience aimed at introducing a complex approach into the final grade of a Brazilian elementary school. The aim is to show the transformation of the conception of space and time from the Middle Ages with the physics of Aristotle to the 20th…

This article presents a tangible model used to help students tackle some misconceptions about enzyme actions, particularly the induced-fit model, enzyme-substrate complementarity, and enzyme inhibition. The model can simulate how substrates induce a change in the shape of the active site and the role of attraction force during enzyme-substrate…

Scientific terms drawn from common language are often charged with suggestions that may even be inconsistent with their restricted scientific meaning, thus posing didactic problems. The (non-linear) historical journey of the word "pressure" is illustrated here through original quotations from Stevinus, Torricelli, Pascal, Boyle,…

In general, mathematical representations such as formulae, numbers, and graphs are the inseparable components in science used to better describe or explain scientific phenomena or knowledge. Regardless of their necessity and benefit, science seems to be difficult for some students, as a result of the mathematical representations and problem…

This article describes the substance, structure, and rationale of a learning progression in genetics spanning kindergarten through twelfth grade (K-12). The learning progression is designed to build a foundation towards understanding protein structure and activity and should be viewed as one possible pathway to understanding concepts of genetics…

Science classroom discourse is inherently multimodal in that scientific meanings are made through an integration of multiple semiotic systems (e.g., language, diagrams, equations). Although some studies have described this multimodal nature, few have examined and explained the relationship between the integration of multiple semiotic systems and…

Creatures from science fiction and fantasy can be used to illustrate key concepts and principles in biology. This article describes a project for a university-level general zoology course wherein the students classify, down to at least the phylum level, "animals" from the Alien Species Wiki (2013). This is an online database of creatures from…

In this article we focus on the concept of concept in conceptual change. We argue that (1) theories of higher learning must often employ two different notions of concept that should not be conflated: psychological and scientific concepts. The usages for these two notions are partly distinct and thus straightforward identification between them is…